#define _CRT_SECURE_NO_WARNINGS 1
#include <cmath>
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include<math.h>
#include<stdlib.h>
#include<stdio.h>
#include<unordered_map>
using namespace std;

class Solution {
public:
    int singleNumber(vector<int>& nums) {
        int ret = 0;
        for (int i = 0; i < 32; i++)
        {
            int sum = 0;
            for (auto& ch : nums)
                if ((ch >> i) & 1 == 1) sum++;
            sum %= 3;
            if (sum == 1) ret |= (1 << i);
        }
        return ret;
    }
};

int main() {
    return 0;
}